GNU is the only operating system developed
specifically to give its users freedom. What is GNU, and what freedom
is at stake?

What is GNU?

GNU is an operating system that
is free software—that is,
it respects users' freedom. The GNU operating system consists of GNU
packages (programs specifically released by the GNU Project) as well
as free software released by third parties. The development of GNU
made it possible to use a computer without software that would trample
your freedom.

What is the Free Software Movement?

The free software movement campaigns to win for the users of
computing the freedom that comes from free software. Free software
puts its users in control of their own computing. Nonfree software
puts its users under the power of the software's developer. See
the video explanation.

What is Free Software?

Free software means the users have the freedom to run,
copy, distribute, study, change and improve the software.

Free software is a matter of liberty, not price. To understand the
concept, you should think of “free” as in “free
speech”, not as in “free beer”.

The freedom to run the program as you wish,
for any purpose (freedom 0).

The freedom to study how the program works, and change it so it
does your computing as you wish (freedom 1). Access to the source
code is a precondition for this.

The freedom to redistribute copies so you can help others
(freedom 2).

The freedom to distribute copies of your modified versions
to others (freedom 3). By doing this you can give the whole
community a chance to benefit from your changes.
Access to the source code is a precondition for this.

Developments in technology and network use have made these freedoms
even more
important now than they were in 1983.

More about GNU

GNU is a Unix-like operating system. That
means it is a collection of many programs: applications, libraries,
developer tools, even games. The development of GNU, started in
January 1984, is known as the GNU Project. Many of the programs in
GNU are released under the auspices of the GNU Project; those we
call GNU packages.

The name “GNU” is a recursive acronym for “GNU's
Not
Unix.” “GNU”
is pronounced g'noo, as one syllable, like saying
“grew” but replacing the r with n.

The program in a Unix-like system that allocates machine resources
and talks to the hardware is called the “kernel”. GNU is
typically used with a kernel called Linux. This combination is
the GNU/Linux operating
system. GNU/Linux is used by millions, though
many call it “Linux” by
mistake.

GNU's own kernel, The Hurd,
was started in 1990 (before Linux was started). Volunteers continue
developing the Hurd because it is an interesting technical
project.

GNU Go is a program that plays the game of Go, in which players place
stones on a grid to form territory or capture other stones. While it can
be played directly from the terminal, rendered in ASCII characters, it is
also possible to play GNU Go with 3rd party graphical interfaces or even
in Emacs. It supports the standard game storage format (SGF, Smart Game
Format) and inter-process communication format (GMP, Go Modem Protocol).
(doc)